Mapping Cyclist Safety in New York City

Is there a relationship between bike path access and cyclist injuries?

Jason Bixon https://jasonbixon.netlify.com (Merkle Inc.)https://merkleinc.com
01-28-2019

I was inspired by this CityLab article detailing the impending transportation crisis due to the MTA L Line shutdown. Specifically, I am interested in observing whether the shutdown contributes to an increase in cyclist injuries due to motor vehicle collisions as about 275,000 L Line riders seek alternatives.

NYC DOT has predicted about 2% of L Line riders to switch to cycling, while about 79% are predicted to move to other subway lines. I could investigate the dispersion of L Train riders to other options as a whole if data is available, but for now I will focus on cyclist safety as it’s more approachable with currently available data.


Let’s start by looking at some performance metrics for the MTA subway network as a whole.

Some of the performance metric definitions are opaque, so I’ll specify where necessary.

Now let’s look at some two-wheeled data.

And now a map of cyclist injuries and deaths over the last few years.


Series: ts_injuries 
ARIMA(0,1,3)(0,1,1)[52] 

Coefficients:
          ma1     ma2      ma3     sma1
      -0.6902  0.0121  -0.2195  -0.5122
s.e.   0.0831  0.1001   0.0821   0.1416

sigma^2 estimated as 337.8:  log likelihood=-651.65
AIC=1313.3   AICc=1313.71   BIC=1328.31

Training set error measures:
                    ME     RMSE      MAE       MPE     MAPE      MASE
Training set -1.589831 15.57204 10.44011 -4.812162 13.84195 0.5500583
                    ACF1
Training set -0.01016123

Planned Updates / Notes:

This is an ongoing project that I am doing in my free time. If you have any constructive criticism please feel free to reach out, especially with suggestions about spatial regression methodology.

Corrections

If you see mistakes or want to suggest changes, please create an issue on the source repository.